Shareholder Report, Average Annual Return (Details) 74200164200_Putnam Income Fund_Class Y_TSR Annual {Class Y}	12 Months Ended	60 Months Ended	120 Months Ended
	Oct. 31, 2025	Oct. 31, 2025	Oct. 31, 2025
Class Y
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Class Y
Average Annual Return, Percent	6.75%	0.04%	2.43%
Bloomberg U.S. Aggregate Index [Member]
Average Annual Return [Line Items]
Line Graph and Table Measure Name	Bloomberg U.S. Aggregate Index
Average Annual Return, Percent	6.16%	(0.24%)	1.90%